OK A couple of comments to get the ball rolling.
First and foremost I liked the ending - it really made me want to know what happens next. It has to be said though that in normal circumstances I wouldn't have made it that far unless I'd been watching in order to critique.

It's quite a good idea for a spoof but it is absolutely essential that the actors play it dead straight if this is to work. The guy in the hoodie just looked like he was smirking and/or about to burst into giggles.

I think you could have done a lot better with the running around the corridor scenes: Whilst you shot from different places, all the shots were from waist hight and mid shots. Not only that but many shots had the heads cut off. Think about doing some close up shots - face looking anxious and/or breathing heavily whilst running, feet running or skidding round corners, hands bouncing off corners when changing direction. This all adds up to more variety of shots and more shots which would also enable you to put a lot of fast edits in - all of which helps add to the action/excitement.

Whilst many of these shots were shot with a tripod (= good) care had not been taken to set the tripod level so we were faced with quite a few shots where the verticals weren't vertical! I'll never tire of saying, if you want fancy angled shot ("dutch tilt") that's one thing, but make sure it is obviously tilted (20-40 degrees). A few degrees off just looks lazy.

As for the tripod - it's probably a good idea to move it out of shot - I was amused to see it in the corridor at 47 secs. And later, you can argue that it is part of the equipment in the classroom but it actually moves (see 2.03 and 2.40). This sort of thing is careless and, as I've just proved, does get noticed. The viewer will believe just about anything so long as you don't leave signs like this which remind him he's watching a film.

My favourite bit was the "man in black" entering the room with a half-baked somersault. Priceless.

Not a bad over all effort. Tim picks up on some good points. I thought you did well with the sound I actually understood all the dialogue which unfortunately is rare with this type of video. So well done for that.

Good narrative but slightly spoilt by the silly voice of the hoodie actor. As Tim said this role needs to be played straight for it to work.

I was impressed you tried the "dolly zoom" this has to be perfect for it to work. BUT I admire your bravery to try it.

It's when the camera is moving away from the subject and at the same time is zooming in to the subject. This action should be timed perfectly so the subject remains still and creates the impression that the background is moving.